Patent GB-1034833-A (GB)
Title: Diester lubricants
IPC: C07C69/34
Filed: 1963-04-10
Abstract: Liquid lubricants comprise esters of a mixture of dicarboxylic acids, each acid having the molecular formula C19H36O4 comprising a straight paraffinic chain bearing one terminal carboxyl group, the other carboxyl group being attached to a secondary carbon atom, there being at least 4 carbon atoms between the two carboxyl groups, and each alcohol having more than 5 carbon atoms, preferably at least 7, wherein the alcohol residues may originate from one or more than one alcohol, and in which each alcohol has a branched aliphatic chain for preference, for example, in particular the following alcohols, 2-ethylhexyl, 3,3,5-trimethylhexyl, isononyl, isodecyl, isoundecyl, or isotridecyl or alcohols obtained by the oxosynthesis from heptene, octene, limonene, dicyclopentadiene, propylene trimer or tetramer or tri-isobutylene.  The carboxylic acid component is preferably derived from one or more unsaturated C18 monocarboxylic acids by the catalytic addition of carbon monoxide and hydrogen followed by oxidation of the addition product or by the catalytic addition of carbon monoxide and steam, and removal of a,w-dicarboxylic acids and other high-melting acids from the product of either reaction.  The lubricating composition may comprise one or more ester mixtures as above or may contain also hydrocarbon oils or one or more ester lubricants of a different type than above defined.  The lubricating compositions may also include oil soluble salts of organic acids for improving thermal stability and resistance to oxidation, anti-oxidants, detergents, stabilizers and dispersing agents known in the art for the formulation of synthetic lubricating oils.  The Specification includes the physical data on products.ALSO:Esters of a mixture of dicarboxylic acids, each acid having the molecular formula C19H36O4 comprising a straight paraffinic chain bearing one terminal carboxyl group, the other carboxyl group being attached to a secondary carbon atom, there being at least 4 carbon atoms between the two carboxyl groups, and each alcohol residue having more than 5 carbon atoms, especially esters in which the alcohol residues originate from one or more than one alcohol, preferably containing at least seven carbon atoms and in which alcohol residues branched aliphatic chains are present, and in particular wherein the alcohols may be 2-ethylhexyl, 3,3,5-trimethylhexyl, isononyl, isodecyl, isoundecyl or isotridecyl, are preferably made from a carboxylic acid derived from one or more unsaturated C18 monocarboxylic acids by the catalytic addition of carbon monoxide and hydrogen followed by the oxidation of the addition product, or by the catalytic addition of carbon monoxide and water, and removal of the a-w dicarboxylic acids and other high-melting acids from the product of either reaction, by methods known for the synthesis of esters.  Further alcohols which may be used are those obtained by the oxosynthesis with heptene, octene, limonene, dicyclopentadiene, propylene trimer or tetramer or tri-isobutylene. The products are useful as components for lubricating compositions for high temperature (see Division C5).